Control systems for vehicles operating on a track

ABSTRACT

A vehicle transportation system operating along a guideway including a control system for regulating the speed and spacing between vehicles operated in the same guideway and utilizing guideway mounted sensors for detecting the presence of a vehicle, in combination with timers regulating the speed of the detected vehicle in relation to a nominal selected speed, and also regulating the spacing of the trailing vehicles in relation to the lead vehicle by regulating the speed of the trailing vehicle. The sensors can be used for controlling the merging of a starting vehicle into a main line at the proper position and also for insuring proper separation at intersecting tracks.

United States Patent Smoot et al.

[451 Nov. 13, 1973 [75] inventors: Charles H. Smoot, Wayzata; Lowell A.Kleven, Bloomington, both of Minn.

[73] Assignee: Unitlo'Systems Company, Edina,

Minn.

[22] Filed: Nov. 30, 1971 [21] Appl. No.: 203,256

[52] U.S. Cl 104/155, 104/149, 246/108 [51] Int. Cl. B60v 3/04 "[58]Field of Search 104/149, 152, 153, 104/155, 134;246/108, 110

[56] References Cited UNITED STATES PATENTS 1,880,149 9/1932 Neale246/110 X 3,242,876 3/1966 Berggren 104/134 I VEH/CLE 3,263,625 8/1966Midis et al. 104/149 Primary Examiner-Drayton E. Hoffman AssistantExaminer-George H. Libman Att0rney-Ra1ph T. Dugger et al.

[57] ABSTRACT the trailing vehicle. The sensors can be used for co'n- 1trolling the merging of a starting vehicle into a main line at theproper position and also for insuring properseparation at intersectingtracks.

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CONTROL SYSTEMS FOR VEHICLES OPERATING ON A TRACK BACKGROUND OF THEINVENTION 1. Field of the Invention The present invention relates toregulating the speed and spacing between vehicles operating on a trackor guideway.

2. Prior Art In the control of tracked vehicles most developments haveconcentrated on vehicles or trains that have on board power supplies,and utilize some signals, either visual or mechanical to regulate thepower supply on the vehicle or train itself to maintain a properinterval between the vehicles or trains, and also in some instances toregulate the speed of the vehicle. With visual signals an operator willadjust the power for the vehicle to adjust the vehicle speed.

In personalized rapid transit systems which operate along guideways, itis desirable to regulate the spacing of vehicles or trains automaticallybecause of the use of many unattended vehicles which lower operatingcosts for these systems. The US. Pat. to Berggren, Pat. No. 3,242,876shows a type of levitated vehicle system wherein an elemental spacingcontrol for individual vehicles is described. The system usesautomatically opening levitating and propulsion valves in a guideway andthe valves are prevented from opening for a preselected time after theyhave once been actuated. This provides a type of spacing control bypreventing vehicles from receiving levitating air if they are too closeto the leading vehicle, but these valves do not regulate or control theactual speed of the vehicles.

Computer controls for tracked vehicles are utilized, and an example ofsuch control is shown in US. Pat. No. 3,403,634 relating to a railwaypassenger vehicle system.

US. Pat. No. 3,408,113 discloses a system that permits the use ofseveral separated segments in a transportation guideway, and whereineach of the segments is used to transport only one vehicle, thus keepinga proper spacing between vehicles.

US. Pat. No. 3,540,378 shows a passive element levitated vehicleutilizing a subplenum chamber which hinders the recharging of theplenums to maintain a spacing between vehicles operating in the sameguideway.

SUMMARY OF THE INVENTION The present invention relates to a system formaintaining the speed of vehicles or trains of vehicles operating on aguideway, and also for maintaining proper spacing between vehicles whenthere is more than one vehicle Operating on the same guideway.

The control system is operated through the use of track mounteddetectors and controls which react to each vehicle on the track in thesame manner, and are used to regulate the speed of each vehicle relativeto the track. In addition, the track mounted detectors are used formaintaining proper spacing between vehicles. The block concept isutilized. There is a stop block, a slow block and an overspeed blockbehind each vehicle that is being controlled. The presence of thevehicle triggers detectors and control mechanism to present the stopblock" zone immediately rearwardly of each vehicle into which no othertrailing vehicle can enter because all drive power is removed and fullemergency brakes applied. The slow speed block is behind the stop block.A vehicle may enter and follow along in the slow speed block, but itwill be propelled at a slower speed than the nominal desired speed for avehicle. The overspeed block follows the slow speed block and will causefollowing vehicles in this block to speed up, and to move closer to theleading vehicle to maintain a predetermined spacing between vehicles.The effectof the lead vehicle on the spacing control is removed from thecontrols following the overspeed block and the vehicles are propelled atthe nominal desired speed.

All of the control units are track or guideway mounted so that eachvehicle is sensed and controlled in the same manner by a particularcontrol member. Therefore if there is an aberration or malfunction inthe control devices, each of the vehicles will be handled in a likemanner and thus the entire system is not neces sarily shut down. Becausethe individual control sections are short, if the controls for one ofthe sections fail a vehicle will generally be able to traverse or coastthrough this section and keep operating on the rest of the track.

The speed control is achieved by sensing the time elasped from theactuation of a vehicle detector in one of the sections until the vehiclethat tripped the detector reaches a detector for a track section fartheralong the guideway or track. If the vehicle reaches the second detectormore quickly than desired, less thrust or propulsive force is added tothe vehicle, but if the vehicle does not reach the second detectorwithin a preselected time, additional thrust or power is supplied to thevehicle to increase its speed. The spacing control is provided byutilizing a signal from the detectors tripped by the lead vehicle toadjust preselected time period of the timers between the vehicledetectors used for speed control and in this way control the speed of atrailing vehicle in relation to the position of the front vehicle.

The safety stop block is provided to stop any vehicles which come tooclose to a lead vehicle and this block zone extends for a set distancebehind the lead vehicle and follows the lead vehicle.

The motive power for the vehicles as disclosed is supplied throughthrust valves which give pneumatic thrust to levitated vehicles and thelevitation air is supplied through separate valves. The valves arenormally automatically actuated by the levitation pressure under alevitated vehicle.

The controls as shown are all pneumatic. The vehicle detectors deliver asignal to inhibit the proper valves from operation and also to startproper pneumatic timers. The pneumatic timers are adjustable in timeperiod to provide proper time intervals for the slow and fast blocks. Inthe stop block following a vehicle all the valves are inhibited (boththrust and levitation valves). Means are also provided for pneumaticallyrestarting a vehicle that has to be relevitated.

The principles of the control can be used with other types of controls,such as electric, and also can be used with other propulsion means andother guideways.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a fragmentary perspectiveview of a typical portion of a guideway utilizing the present inventionshowing a vehicle moving therealong;

FIG. 2 is a schematic plan view of a guideway divided into guidewaysections according to the present invention and showing schematicallythe controls used therefore;

FIG. 3 is a fragmentary perspective view of a portion of a vehicleguideway showing a vehicle detector mounted thereon;

FIG. 4 is a schematic representation of a graph showing the speedcontrol function at different sections of the guideway of the presentinvention in relation to a vehicle on the guideway;

FIG. 5 is a schematic representation of one set of controls for thepresent invention;

FIG. 6 is a cross sectional view of the vehicle detector shown in FIG.3;

FIG. 7 is a schematic representation of a typical pneumatically operatedtimer that has a variable time period and which is used with the presentinvention;

FIG. 7A is a fragmentary enlarged view of a shuttle valve type OR gateused with the pneumatic system of the present invention;

FIG. 7B is a sectional view taken as on line 7B7B in FIG. 7;

FIG. 8 is a sectional schematic representation of a start-stop moduleused for pneumatically starting vehicles with the present invention;

FIG. 9 is a sectional view of a control utilized for adapting the systemto use with trains of vehicles comprising several vehicles hookedtogether;

FIG. 10 is a schematic representation of an acceleration lane formerging vehicles into a main guideway and also a schematicrepresentation of intersecting guideways; and

FIG. 11 is a schematic representation of pneumatic connections necessaryto control the main guideways and merging guideway.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring first to FIG. 1, asimplified layout of a typical guideway assembly and vehicle arrangementwith which the present invention is utilized is shown. It should beunderstood, of course, that the preferred embodiment discloses merelyone form of vehicle and track or guideway assembly which can be utilizedwith the present invention. Other guideways, or other types of vehicles,including trains as explained subsequently, can be utilized, andadvantageously use the principle of the speed and spacing control hereindescribed.

A guideway illustrated generally at 10 includes a pair of upstandingguide walls 12,12 and a transverse support wall 13 extending between theguide walls. Underneath the support wall 13 a second wall 14 is formedto form a plenum chamber 15 that carries levitation air under pressurefrom an air pressure source (not shown).

The floor 13 has a plurality of cruise or levitation valves 11 therein,and in the center of the guideway there are a plurality of thrustervalves or thrust section valves illustrated generally at 16. The valves11, and if desired the valves 16, are of 'the type generally disclosedin U.S. Pat. No. 3,685,788, Issued Aug. 22, 1972. The thruster valves 16are provided with nozzles which provide a thrust to a vehicle over thevalves, while the cruise valve or levitation valves 11 are made so thatthe outlet opening provides very little propelling force.

The valves are normally automatically opening in response to a pressuresignal from a levitated vehicle as shown in the aforesaid U.S. Pat. No.3,686,788. Each of the valves is locked into place in the deck 13 asshown in that patent application and controls flow of air under pressurefrom the plenum 15 to the plenum chamber formed under vehicle 25. Inaddition these valves can be opened at any time or held closed when avehicle is above them by control signals which can be carried bycompartmented ducts 17 and 18 as shown and explained in U.S. Pat. No.3,685,788, which is incorporated herein by reference. For control ofspeed the guideway is divided into sections, and the valves in eachsection are ducts 17 and 18 respectively open to a separate compartmentso signals in the duct can either keep the valves closed by placingpressure control signals on the valves, open the valves at anytime byuse of a vacuum control signal, or permit-the valve to respondautomatically to the presence of a vehicle and open when a levitatedvehicle pressure signal is present above the valve. A plurality ofcontrol conduits shown typically at 21 and 22, respectively, are used tocarry pneumatic pressure signals to the valve control compartment inducts 17 and 18 for various functions.

The guideway or track 10 is made to provide guidance for the vehicle 25,which is shown as a passive vehicle meaning that there is no on boardpower supply. The vehicle 25 can have suitable walls, doors and seatsfor carrying passengers in a system or for transporting freight. Thevehicles 25 have plenum chambers underneath, and the levitating valves11 and thrust valves 16 are automatically operated in response topressure signals so that they open when a vehicle having levitationpressure underneath the vehicle is in the area of the valve. The plenumchamber design is preferably of the bag seal type of the type generallyshown in U.S. Pat. No. 3,321,038. In this instance, usually there arefour or more plenum chambers formed with separate flexible bag sealsthat inflate when they are under pressure, and which permit a smallamount of air to escape from underneath the vehicle, but keep thevehicle levitated.

In a usual system, a length of the track 10 is used, and the vehiclewill be levitated by the levitation valves 1 1, and the additionalthruster valves 16 which provide a thrust to the vehicle to propel itforwardly so that there is air levitation and propulsion. The airpressure and power source is completely apart from the vehicle. Thenumber of thrust valves 16 used can be varied as desired, and some ofthe cruise valves can also supply thrust for normal speed operation withthe separate thrust valves used only when the vehicle is too slow. Thethrust valves here are shown only schematically and of course thevehicle can have thrust reaction devices or vanes thereon to aid inpropulsion. Also, special thruster sections such as those shown in U.S.Pat. Application Ser. No. 90,257, Filed Nov. 17, 1970, now U.S. Pat. No.3,718,096 for Vortex Thruster For Fluid Propelled Objects can be used.

In transportation systems, where there is a long track or guideway and anumber of individual vehicles are operating along a length of trackbetween passenger stations, or vehicle berths, or, where there are aplurality of trains of vehicles each made up of a plurality of vehiclescoupled together, it becomes important that a proper spacing between themoving modules whether an individual vehicle, or a train of coupledvehicles is maintained. Also for efficiency it is necessary that therelative speed of each of the modules, whether it is an individualvehicle or a train, is kept within a desired design limit in order tomaximize the utilization of the guideway installation and move a large,number of people in a short space of time. When the vehicles areautomatically operated as in the present device, with no on boardcontrols for power to the vehicles, it means that the control devicesmay be track located and used to actuate other devices to insure that noaccidents occur. The vehicles in the form disclosed play an essentiallypassive role in controlling their spacing and speed. While in the formdisclosed the thrust and levitation controls come from track or guidewaybased valves, it is desirable in some instances to utilize on boardpower for thrust and levitation of the vehicle which can be controlledby signals from the track by suitable means. The latter control systemis still track based, utilizing vehicle sensors and other controlmodules to insure that there are no accidents.

In accomplishing the purposes of the present invention, the guidewayused with the vehicle system is divided into a plurality of guidewaysections. This sectional system is the basis for controlling both thespeed and spacing of the vehicles. FIG. 2 shows a schematicrepresentation of a length of guideway that represents the sectionalsystem layout.

In FIG. 2 individual sections are marked off and numbered for referencepurposes. The vehicles as disclosed, are made to be just slightly longerthan an individual guideway section. The section length can be selectedas desired, however, and in the form shown, each of the sections is 13%feet long, so that four of the sections amount to 55 feet in length. Thevehicles, for example could be 15 feet long in this arrangement.

The nominal track speed selected for movement of the vehicles forillustrative purposes is feet per second. The vehicles are provided withunder the surface brake skids so that if the vehicle delevitates becausethe levitation and thruster valves are shut off the skids will engagethe top surface of deck 13 of the guideway and will slide to a halt. lf0.3 co-efficient of friction between the vehicle brake skids and theguide-way operating surface is provided, at 30 feet per second velocityat vehicle requires approximately 46 feet to stop. Thus delevitating thevehicle is a means of applying a braking force to the vehicle. 1

Each of the sections of the guideway, which are 13% feet long, generallyhas a vehicle detector at the first end thereof in relation to normaldirection of vehicle movement. The sections shown are numbered 32through 56. This vehicle detector is for each section designated with anA suffix and there is a separate vehi cle detector at the start of eachof the sections. The detector 53A is shown at the starting line of thesection 53, and there are detectors 52A, and 54A, and a separatedetector for each of the sections. As shown schematically, a leadvehicle 57 is entering the section 53, and has just intercepted thedetector 53A. The vehicle is traveling in the direction as indicated bythe arrow 58. A following vehicle illustrated at 59 is also beingcontrolled by the overall speed and spacing system, and has just enteredinto the section 44, and of course this has tripped the vehicle detector44A.

The vehicle detectors are shown schematically in FIG. 2. They can be anytype of detector such as a photocell, an electrical trip signal,magnetic signal, radio frequency signal or pneumatic signal. The vehicledetectors are mounted on the track or guideway, and are made so that thepresence of a vehicle will cause a signal output from the detector forcontrol purposes.

FlG. 3 shows a pneumatic vehicle detector in perspective view. Theguideway side wall 12 has a small opening 60 therein through which apneumatic nozzle 61 protrudes, and a jet of air indicated at 62 isdirected toward a vehicle detector member in this case 53A. The detectormember has a center recess 62A with a sender nozzle 63 on one sidethereof, and an aligned receiver 64 on the opposite side thereof. A jetof air indicated at 65 is normally emitted from the nozzle 63 toward thepressure receiver 64, but the jet of air indicated at 62 strikes anddeflects the jet of air 65 so the air from nozzle 63 does not strike thepressure receiver 64. When there is no vehicle over a detector thereceiver 64 receives no pressure. When the vehicle is in place over thedetector, the jet 62 is interrupted by the presence of the vehicle. Thenozzle 61 is placed so the air jet from it will strike the vehicle. Thejet 65 will then strike the pressure receiver 64. The vehicle detectoras will be more fully explained, will be activated to deliver an outputpressure signal in a pneumatic system which can be utilized to controlspeed and spacing of following vehicles. The vehicle detector can takeany number of desired forms for electrical or hydraulic actuation. Thepneumatic system shown is a simple fluid amplifier type of system todeliver a pneumatic output when a vehicle is detected at the beginningof each of the guideway sections. The source of air pressure for boththe jet 62 and jet 65 are from the pressure source for plenum chamber 15so that no other external air needs to be provided.

The basic speed of the vehicle 57, for example, is determined by thethrust that is provided by the thruster valves. in normal operation thelevitation valves will be automatically operated to keep the vehiclelevitated unless an emergency stop is indicated. The speed can becontrolled by either turning on the thruster valves, in any particularsection of the track as the vehicle traverses a guideway section, orleaving the thrust valves off during the time that the vehicle istraversing a section of guideway. In order to accomplish thrust control,a separate timer is associated with each of the respective guidewaysections. The timer has an output signal during its time period and ifthe time period lasts longer than the time interval of vehicle transitfrom the detector which started the timer to the detector of theguideway section associated with the timer, the output signal is used toinhibit the thrust valves on that guideway section.

As shown schematically in FIG. 2, a timer 55B is started at the time thedetector 53A is tripped. Thus the timer two guideway sections ahead ofan activated vehicle detector is the one started, each time a vehicletrips or activates a vehicle detector such as 52A, 53A, or 54A. Again itis to be remembered that each of the guideway sections has a separatevehicle detector associated therewith.

The vehicles 25 are designed to be traveling at a desired nominal speed,as previously stated, for example 30 feet per second. Therefore the timefor a vehicle, moving at its nominal speed, to go from the vehicledetector 53A to the vehicle detector 55A is known. The nominal value ofthe timer eriod of the timer 558 (the elasped time that it norma lycounts) will be the same as the time necessary for a vehicle at itsnominal speed to go from detector 53A to detector 55A. If the timer timeperiod has not run out before detector 55A is activated, the timersignal is used to inhibit the thrust valves in section 55 of theguideway. This means that the lead vehicle 57 will not receiveadditional thrust in section 55, as long as the vehicle is running atits nominal speed or faster. This lack of additional thrust will cause avehicle to slow down slightly, and if necessary further speedcorrections can be made as the vehicle traverses the next guidewaysection. For instance if the vehicle runs below nominal speed, the timerperiod will have run out and thrust will be provided in that section tospeed up the vehicle. The timers associated with each of the'guidewaysections are sequentially initiated by the detectors two sectionsupstream. The time period for the timers are varied to accomplishdirectly the proper speed and indirectly the spacing of vehicles.

When the lead vehicle 57 enters the guideway section 53, and detector 53A is initiated, the vehicle 57 will actually be occupying the tracksection 52. The next four track sections to the rear of track section52, namely sections 48, 49, 50 and 51 will receive a signal fromdetector 53A that inhibits both the cruise and the thrust valves inthese sections to stop any vehicle which enters these sections. If awheeled or tracked vehicle was controlled the brakes would be applied.When the valves shown in US. Pat. No. 3,685,788 are used, a pneumaticpressure signal from the vehicle detector 53A is introduced into theproper compartments of ducts 17 for the cruise valves and in the propercompartment of duct 18 for the thrust valves to keep the valves in aclosed position by applying a pressure signal on valve controldiaphragms shown and explained in US. Pat. No. 3,685,788. This preventsthe valves from automatically opening even if a vehicle is detected bythe sensing port of the valve, which normally would cause opening. Thus,the four guideway sections trailing the occupied section is termed astop block" and is indicated in FIG. 2. This is a digital four (or otherselected number) section block-that follows behind a vehicle as thevehicle intercepts each equential vehicle detector. For example, whenthe vehicle detector 54A indicates that the vehicle 57 (as shown thelead vehicle) has reached the track section 54, the stop block wouldthen become sections 49, 50, 51 and 52. The use of the stop block ismade to insure that if a following vehicle such as 59 comes too close tothe lead vehicle, all levitation and thrust air will be denied thevehicle. The vehicle will come to its stop against the track surface onbrake skids provided on the vehicles. The stop block, which comprisesthe four guideway sections behind a vehicle (or a train if trains areused) is part of the spacing control system.

After the stop block, which is on a digital basis, has passed aparticular track section, the timer that is tripped by the detectorassociated with the guideway section that is the last section in thestop block, for example as shown in FIG. 2, the timer 50B, receives asignal from detector 53A and a mechanism or device is utilized foradjusting the time period of the timer 50B for a longer time period thanthe normal time period. The time period of the timers actuated bydetectors for four (or other selected number) guideway sections behindthe stop block have their time, period set longer than normal. Thismeans that in the guidway sections associated with the timers tripped bydetectors 44A -47A, which are timers 46B 50B, the vehicle speed has tobe slower than nominal or else thrust will be-de-,

nied when the vehicle reaches the corresponding guideway section. Eachtimer of each section in the slow block has a different time setting,varying from the time for the slowest desired vehicle speed at timer 508to the time for nominal vehicle speed at timer 46B. The speed of avehicle in the slow block just short of the stop block would becontrolled to the minimum desired speed of 28 feet/sec, as disclosed. Asthe forward vehicle (traveling at a nominal 30 feet/sec.) moves awayfrom the trailing vehicle (traveling at 28 feet/sec.) the trailingvehicle moves farther back in the slow block where the timer periods areset for a time period to provide a higher vehicle speed. The vehiclewill then speed up to its now speed setting. However this speed is stillbelow nominal, so the trailing vehicle will still fall further behindthe lead vehicle. This action repeats until the trailing vehicle reachesthe position where the timers are set for nominal speed, then bothvehicles will travel at the same speed and maintain fixed spacing.

Then, for 10 sections behind the slow block there is a overspeed block"as shown ranging from sections 34 through 43. The timer in each of thesetrack sections which is activated by detection of a vehicle is set for ashorter time period than the normal time period. This time period isalso set in response to a vehicle detector signal ahead (upstream) ofthe timer so that the adjusted time period is in effect after thepassage of the stop block and slow block. For example the timer 428 willbe set for a shorter time period than the timer 55B (if 553 is atnominal time), and it will be set so that if the vehicle which startsthe timer 42B by tripping detector 40A is not going at least 32 feet persecond (which is over the nominal speed of 30 feet per second in theexample given) the thrust valves for the block 42 will be initiated whenthe vehicle reaches section 42. This speeds up the vehicle slightly andkeeps it from dropping back farther from its desired spacing. Afollowing vehicle thatis close enought to a leading vehicle to beunderits influence will therefore follow a lead vehicle just ahead ofthe overspeed block and near the rear or trailing end of the slow block.

The timers for each of the sections behind the overspeed block will beset for their nominal time period, just as timer 55B, and a vehicle thatis behind the overspeed block is not influenced by a leading vehicle,and of course is not close enough to a lead vehicle to be in danger ofcollision.

The means for changing or adjusting the time period of the timersoperation on an elasped time basis. In other words, the adjusting meanswill set the timer time period to be longer than normal for a length oftime equal to the time necessary for a vehicle to traverse four guidewaysections at its nominal speed. Thus if the nominal speed is 30 feet persecond, and the four guideway sections comprise 55 feet, as explained,each of the timers would be set to have a time period longer than normalfor slightly less than 2 seconds. Then, if the nominal vehicle speed isagain approximately 30 feet per second, for the next five seconds,approximately, the timer period is shorter than normal so that if thevehicle did not travel at a higher speed when under control of theshorter period timer, it would receive thrust. After that, theadjustment device for the timer period returns to its normal conditionfor anyadditioal vehicles. Instead of changing the timer time periodsetting on a time basis, the'setting device for the timer time periodmay also be changed in response to vehicle position relative'to theguideway section associated with the timer using vehicle detectors toadjust the timer period.

It is in this manner that the spacing of the vehicles is maintained. Thegraph in FIG. 4, shows the vehicle speed graphically on a time elapsedbasis from the time the timer period setting device is tripped. Thetimer period function inversely follows the speed (the shorter the timeperiod, the greater the speed). The timer period is a decreasingfunction vertically on the graph.

As shown in FIG. 4, for the four sections immediately after the stopblock the vehicle speed will be held below nominal speed, and isindicated by the graph line 66. The speed increases (time periodshortens) with an increase of time. The nominal speed line is indicatedby the dashed line 67. The vehicles will travel at over nominal speedfor the next ten sections of the guideway and this line is indicated at68. Along line 68 the time period of the timers will be shorter so thatit will in effect require the vehicles to be going faster in thesesections. Then the timed speed will drop down to the nominal speed afterthe overspeed section has passed.

In FIG. 5, a logic diagram is shown for the system in connection withvalves for section 53 which is triggered by the signal from detector51A. The overall control is generally shown in FIG. and includes astart-stop module 72, a timer module 53B, a vehicle detector module 55Aand when there is more than a single vehicle, a train module 73 isconnected into the system to prevent stopping of the vehicles that areimmediately behind the lead vehicle in the train. The control port ofthe cruise valves in section 53 are represented by a symbol shown at53C, and the control port of the thrust valves are represented by asymbol shown as 53D. Again, the cruise valves are utilized forlevitating the vehicle and the thrust valves are used for acceleratingthe vehicle up to the desired speed, or could be used for deceleratingthe vehicle if they are oriented to provide deceleration.

In the automatic control system which is to be described as a preferredform of this system It should be noted that the pneumatic signal alongthe line 74 leading to the cruise valves or along the line 75 leading tothe thrust valves will inhibit these valves to prevent them fromoperating.

Because the device under consideration here is shown in connection withthe track section 53, timer 53B is shown. The timer $38 was started whenvehicle 57 tripped detector 51A.

The start-stop module 72 is a control that is utilized to insure thatthe cruise valves for section 53 are inhibited, and also that the thrustvalves in section 53 are inhibited when there is the presence of avehicle detector signal in any one of the four sections (55, 56, 57, 58)of the guideway ahead of the unit. In other words when the section 53 ispart of the stop block, the cruise valves will be inhibited.

Further, the start module is utilized to restart a vehicle if thevehicle has been stopped on the track, for example, if the vehicleenters the stop block and delevitates. Because the valves used open inresponse to a pressure signal under the vehicle, when the vehicledelevitates this signal is gone and the valves will not reopen unlessindependently operated. The start module supplies a negative pressuresignal to the control diaphragm of the levitation (cruise) valves toopen them and start the vehicle.

The start-stop module 72 includes a four input OR gate 76 which receivessignal inputs from the vehicle detectors 55A, 56A, 57A and 58A and theinput lines are labeled 55AL 58AL for identification. The OR gates usedhere are designed to take pneumatic signals from these detectors, and ifthere is a signal from any one of the coupled detectors, the OR gate 76delivers an output along a line 204 through a fluid amplifier valve 78and line 77 to inhibit the cruise valves 53C and as will be explained toalso act to inhibit the thrust valves 53D in associated with componentsforming a part of the timer module.

The fluid pressure signal from detector 54A on line 54AL, indicating avehicle at the start end of guideway section 54, goes into an OR gate79. All of the signals referred to are fluid under pressure in the formshown. Also, the output of the detector 53A is connected with a tube orline 80 to the second input of OR gate 79. The OR gate 79 is connectedto a time delay mechanism 81 of suitable form which operates through anamplifier 82 to energize a venturi arrangement 83 to create a vacuumthat will be passed along line 77 to cause the cruise valves 53C to openafter the preselected time delay has passed if a signal is present online 54AL or line 80 (and if there is no input to OR gate 76). Theinputs to OR gate 76 override any start signal from the venturiarrangement.

The timer module 53B includes a basic timer means, along with itsvariable set point mechanism which is shown schematically at 87. Thesignal from the detector 56A is transferred with a line 90 to the inputof the basic timer 87, and this signal on line 90 starts the timervariable set point into operation as will be more fully explained. Thetripping of the timer 53B to set the timer running is down by a signalalong a tube or line 51AL that is the output of the detector 51A at thetime the vehicle 57 passes the detector. During the time period of thetimer, the timer has an output pressure signal along the line 92 thatgoes into an OR gate 93. The other input of the OR gate 93 is the outputof the AND gat 85, and the output ofOR gate 93 is also connected to oneinput of the AND gate 85. It should be noted therefore, that if detector53A has an output along line 80, it will pass through OR gate 79, andwill also deliver a signal along line 84 to one input of the AND gate85. Thus, if there is an output from the timer which is coupled to theother input of AND gate 85, (meaning the time period set has notelasped) there will be an output from the AND gate along a line 95, andthis will go into one input of an OR gate 96, through an amplifier 97 tothe thrust valves 53D to inhibit these thrust valves. The inhibit signalwill remain because AND gate 85 will continue to deliver a signal untildetector 53A or 54A is no longer actuated because the output of AND gate85 locks the AND gate through OR gate 93. However, if the timer periodon timer 87 has elasped, there will be no output on line 92, andconsequently the AND gate 85 will not have an output so that the thrustvalves will not be inhibited, but will actuate to provide thrust to thevehicle in a normal manner.

The inhibiting signal from the OR gate 76 that goes through amplifier 78also enters OR gate 96, so that if there is an inhibit signal eitherbecause a vehicle is in the stop block which is evidenced by thepresence of signals from the detectors 55A 58A on OR gate 76, or ifthere is a signal present from the AND gate 85, the thrust valves 53Dwill not actuate.

It should be noted that the timer varying set point cycle is initiatedto be effective for vehicles in guideway sections after the dead blockfor a leading vehicle has passed. For example, the timer 87 of module53B will be tripped by a signal from detector 51A, and therefore theadjustable set point cycle for this timer 87 of section 53 is commencedat the time that detector 56A is tripped. A vehicle being timed by timer87 is at least four unoccupied guideway sections behind the vehicle thattripped the detector 56A and thus is behind any stop block. The timerwhose time period is being adjusted is two sections ahead of the end ofthe stop block, because the vehicle being controlled is still twosections away and out of the stop block.

The detector 53A signal, in addition to being passed along line 80 issent through an output line 100, and can be directly applied to OR gatessuch as OR gate 76 and the OR gate 79 in control modules for dead blockbehind vehicle 57. For example, the output of detector 53A goes to thestart stop modules in sections 48 through 52. The output line 100 alsois connected to the set line in the timer 55A to commence the basic timeperiod running for this timer.

When a train of vehicles is utilized, a train module il-' lustrated at73 is used which includes a blocking gate 101 that receives a controlsignal from the detector 52A so that as long as there is a signal at52A, the stop block signal cannot be passed rearwardly along line 101A.If the module is a train of vehicles, the stop signal would continue tobe present until the train had cleared the detector 42A, at which timethe signal from the detector 53A can be applied to the sections at the'rear of the train for the stop block behind the train. A

line 102 may also carry a signal from the detector 53A to the OR gate 79of section 54 and the other line shown branching from line or tube 100can be used for tripping the timer 55B.

If the vehicles are substantially shorter than the guideway sections,then more than one vehicle detector must be used in each section. Thisalternate connection is shown by dotted connection in FIG. 5. The boxesshown at 91 represent threevehi cle detectors for the same guidewaysection which deliver their output signals into a three input OR gate91A which would alternately supply the pressure signal for lines 80 and100. A signal from any of the three detectors connected to' OR gate 91Awould provide the detector signal in place of the detector 53A. Thiswould in effect couple each detector 91 with the other detectors in theguideway section so that at least one detector 91 would provide anoutput for lines 80 and 100 as long as the shorter vehicle was still inthe guideway.

In FIG. 6, a sectional view of the vehicle detector, for example 53A isshown. The deck 13 is shown in place, and the detector 53A has a recesswith the nozzle 63 at one side thereof. The nozzle 63 provides air in ajet indicated at 65, that is directed across the recess toward thepressure receiver port 64. The nozzle 63 is supplied with fluid underpressure through a passageway 105 that is open to the plenum chamberbeneath the deck 13. This constant source of air in the plenum chambersupplies the jet 65 through thenozzle 63. When the jet 65 is divertedfrom the receiver by jet 62 (see FIG. 3) the device is in the state asshown in FIG. 6.

When the jet 65 is not striking the pressure receiver, a diaphragm 106,which is made to. divide an internal chamber in the detector, is biasedwith a spring 107 to close off a passageway 108, that is open through arestriction 109 to the pressure passageway 105. A chamber 110 ispressurized on one side of a diaphragm 111 through restriction 109 sothat the diaphragm biases a headed valve 112 (as will be shown typicallylater) to keep a passageway 113 leading from the plenum chamber 15closed off. It should be noted that a passageway 114 is provided to theupper surface of the deck 13, so that the signal pressure underneath thelevitation pads of a vehicle also acts on the bottom of diaphragm 111.When a vehicle is over the detector unit, the jet 65 is permitted to gointo the pressure receiver 64, which pressurizes the chamber of thepressure receiver, and moves the diaphragm 106 away from the opening inthe passageway 108, against the action of the spring 107. This reducesthe pressure in chamber 110 and valve 112 opens moving the head awayfrom the passageway 113, thus opening the passageway 113 to a chamber116 on one side of a diaphragm 117 of an amplifier valve 118. This valve118 will then be moved in direction as indicated by the arrow 119 (itpreviously will be closed because of plenum pressure on head 118A) andthis then opens a passageway for fluid under pressure to come from theplenum chamber or duct past head 1 18 out through the output line 53ALof the vehicle detector 53A. It is this output from line 53AL thatprovides a pressure signal to indicate that the detector has detected avehicle above it. This pressure signal is used, as shown in the logicdiagram of FIG. 5 in the line 100 and line 80. This is a typical vehicledetector, and the output signal comprises a fluid flow under pressureused as a signal to activate further modules as described.

Referring now to FIG. 7, an example of a specific timer module 538 isshown part schematically. The components that are shown in FIG. 7 andalso shown in FIG. 5 are numbered alike.

The timer is shown in its rest position and is basically composed of amonostable multivibrator (which is a one shot), an AND gate, the inputfrom two vehicle detectors, the output of the timer to the thrust valves(or the OR gate 96) and the signal line for starting the variable timesequence (set point signal 90) together with the associated mechanismfor varying the time of'the one shot; The one shot is composed of twoinverting valves, three diaphragm swept volume chambers, which may bereferred to as pneumatic capacitors, an OR gate, and the necessarybleed, orifices and check valves. This is a fully pneumatic timer, andof course there are electronic equivalents as well as mechanicalequivalents which have variable periods of time to which they can beset.

The basic timing diaphragm swept volume timer housing is shown at 125,and comprises ahousing havinga diaphragm 126 extending thereacross,forming two chambers and having a first input line 127 and a second line128 leading therefrom. The line 128 has a restriction orifice 129 at oneend thereof, and this orifice is open to duct pressure, or in otherwords to a source higher than atmospheric pressure. In addition, theline 128 is connected into a line containing a restriction orifice 130that leads to atmospheric pressure at its outer end. A line 128 alsoopens to a control housing 131 that has a diaphragm 132 dividing thebase of the housing into two chambers, and the chamber on the side ofthe diaphragm 132 opposite from the opening through line 133 (which isconnected into line 128) is open to atmospheric pressure through apassageway 134. Diaphragm 132 is attached to control sliding valve 134A,which is shown typically in FIG. 7B, that seals around an opening 136leading to duct or plenum pressure. It should be noted that when theplenum chamber is pressurized, these openings can merely be open rightto the duct pressure. Thus, in the quiesent or at rest stage of thetimer, the valve 134A is held closed by the pressure on diaphragm 132set up by the ratio of orifice or restriction 129 to restriction 130.The output line 92 as shown in FIg. 5 leads from the chamber 137 inwhich the valve head 135 operates.

A further control of the timer is a valve housing 140, which has a firstchamber 141 and a port or passageway 142 leading from duct pressure intothis chamber 141. Flow through the passageway 142 is controlled by valve143, and the line 127 to the basic timer housing 125 is connected tochamber 141 to carry the pressure coming through the passageway 142 tothe basic timer housing when the valve is open. In its quiesent stage,as shown, the valve 143 is open, and this seals off the passageway forthe valve phank so that fluid under pressure cannot flow down into thesecond chamber 144 of the housing 140. Second chamber 144 is dividedwith a diaphragm 145, and on one side of the diaphragm 145 there is apassageway 146 leading to atmospheric pressure. On the opposite side ofthe diaphragm 145 from the valve 143, there is a shuttle valve or ORgate illustrated generally at 147. The shuttle valve is typical of theOR gates shown schematically in the logic diaphragm of FIG. 5. As showntypically in FIG. 7A, the set input line 51AL and a second line 148 arealigned axially, and each has small guide knobs 149 and 150,respectively, adjacent their ends. A small disc 151 mounted onto a shaft152 that is slidably mounted in the ends of and is guided by the knobs149 and 150. The disc or button 151 can thus slide axially to close theopening to either tube or line when a fluid under pressure flows intochamber 144A from the other tube.

Just by way of example, when fluid under pressure comes in through theline 51AL from a vehicle detector that trips the timer, a button 151would slide to the left as shown in FIG. 7 and 7A to close off'theopening to the tube 148, and cause pressure to rise in chamber 144A andact on the diaphragm 145 moving the valve 143 upwardly so that the headof the valve 143 closes off the passageway 142. The line 148 is turn isopen through a check valve 153 to a diaphragm formed chamber which willbe more fully explained.

In the at rest stage, however, as shown in FIG. 7, the input throughline 51AL is zero, and its output through line 127 is high, moving thediaphragm 126 inthe basic timer housing 125 all the way to the end ofits movement. The basic time period of the timer is controlled bymovement of diaphragm 126 and its effect on valve 134A.

Varying the time period for diaphragm 126 to sweep across timer 1.25 isaccomplished as shown with a pair of housings having sweep diaphragmchambers that are connected to the line 128. As shown, a line 157 isopen to the line 128, and a restrictive orifice 158 is contained in thisline. This orifice 158 can be of any usual or suitable design asdesired. The line 157 leads directly into a chamber 159 formed in ahousing 160 having a sweep diaphragm 161. An additional branch line 162is connected to the line 157, and has a restrictive orifice 163 therein.The line 162 leads into a chamber 164 of a housing 165 which has a sweepdiaphragm 165A and a spring 166 between the top of the housing and thediaphragm 165A in the chamber 164. The chamber 164 is also connectedthrough a check valve 167 and a tube or line 168 to the set point line90. The set point line 90 is the line leading from the detector 56Athree sections ahead of the section 53. The line 90 opens through acheck valve 169 to a chamber 170 which is on the opposite side of thediaphragm 161 from the chamber 159. Also, it should be noted that theline 148 is open through check valve 153 to this chamber 170, and arestrictive orifice 171 is provided leading from the chamber 170 toatmospheric pressure. The check valves here are shown merely as hingedgates over the ends of the tubing or lines utilized, but could be anydesired check valve.

In addition, it should be noted that the line 148 is connected into thetube or line 92 so that the pressure output of the chamber 137 is feltboth at line 148, and the OR gate 147, as well as through the line 92 tothe OR gate 93.

The entire timer component is used in the timing circuit with an ANDgate, coupled to an OR gate. The AND gate is shown at 85, and the inputfrom line 84, which comprises the output of the OR gate 79 is applied tothe input of AND gate 85 through a valve 175, which controls flow into achamber 176 and thus through a line 177 back to a chamber 184 that isformed in the housing 179 with a diaphragm 180. This chamber 184 is partof OR gate 93. A chamber 178 on the opposite side of diaphragm 180 isopen to atmospheric pressure through a passageway 181. A valve head 183can move to permit or to close off, flow between chamber 176 and 178.Chamber 184 is an OR gate chamber for OR gate 93 which comprises ashuttle valve, including a disc 185, moving between the end of tube 92,and the end of tube 95. The tube or line 177 connects into the line 95.The AND gate will lock on because of the feedback signal through line177 to OR gate 93.

The typical valve construction is shown in FIG. 7B and shows how theshanks of the valves are made to permit flow of fluid along the shanks.For an initial examination of the operation of the timer, therestriction or orifice 158 is assumed closed. Also assume for the firstdiscussion that the check valve 153 is held closed to prevent the outputof chamber 137 from entering the housing 160. When a vehicle detectorputs in a pressure signal or sustained pressure along line SIAL, thisstarts the timer running. The OR gate disc 151 will close against theend of tube 148 and the diaphragm 145 will be actuated to lift the valve143 and close off the passageway 142 leading from duct pressure. Theoutput of fluid under pressure through line 127 is thus reduced to zeroand the diaphragm 126, which has been in the position shown in FIG. 7starts to move toward the end of tube 127 because of pressure coming inthrough restrictive orifice 129. The pressure then in tube 128 actuallyreduces substantially to zero from duct pressure which had built up inthe tube 128 through orifice 129 and at this stage there is essentiallyno flow in the orifice 130.

This reduces the pressure on diaphragm 132 because of the connectionthrough the tube 133, so that the valve head 135 moves away fromposition closing off the passageway 136, and letting duct pressure flowthrough chamber 137, and into line 92 and line 148. The head 135 sealsoff the chamber 137 on the valve side of diaphragm 132 to lock on the ORgate through line 148 and hold valve 143 closed if the pressure signalin line 51AL was only a pulse. This would move the disc 151 against thetube 51AL, assuuming that the signal in line 51AL was no longer present,and would hold the valve 143 closed because of the pressure coming fromchamber 137 through line 148. Also, this pressure signal moves the ORgate 93 so that the disc '185 blocks off tube 95, and the diaphragm 180is actuated to move the valve shank 182 upwardly, moving the head 175away from the passageway surrounding the valve, and if there is apressure signal in the line 84 from the OR- gate '79, (which is madelike the OR gate 93) this pressure signal would be carried throughchamber 176 and tube 177 to lock the valve head 175 open. The pressuresignal from line 84 will then appear on the line 95, and will be used toinhibit the thrust valves through the OR gate 96 and amplifier 97. TheOR gate 96'includes a shuttle valve and is just shown as a block. Theother input to the shuttle valve for OR gate 96 is the line 77. Thisshuttle valve in turn controls the amplifier valve 97 that controls flowof fluid from the duct pressure to the thrust valve inhibit controls. Ifno start-stop module is used with the system, the output of line 95 canbe used to directly inhibit the thrust valves of the section that isbeing inhibited.

All this action is occurring while diaphragm 126 is moving toward tube127. After the diaphragm 126 reaches the extent of its travel towardline 127, the pressure in line 128 will rise immediately, as will thepressure in line 133, causing the diaphragm 132 to move the valve head135 up against the passageway 136 to close off the output from chamber137. As soon as this output from chamber 137 is removed from the linebranch 148 leading to the OR gate 147, if there is no longer any signalon line 51AL, the valve 143 will open and the output from chamber141will again go to duct pressure causing the diaphragm 126 to return toits solid line position. The time during which there is an output fromthe chamber 137, or in other words the time the valve 135 is away fromthe passageway 136, is the timing interval. It should be noted that thediaphragm 126 of timer housing 125 will not be reset even through theoutput from chamber 137 is low, if there is still a signal on line 51AL,until this signal is removed to permit the valve 143 to move to itssolid line position so that duct pressure is applied through the tube127 to the diaphragm 126.

The operation of the unit is much the same with the time period changinghousings 165 and 1611 added into the pneumatic circuit. in the pneumaticcircuit, the restriction 158 prevents large increases in pressure attube 128 from movements of the diaphragms in housings 160 and 165. Thetime of operation of the basic timer diaphragm 126 is dependent upon theposition of the diaphragms in housings 160 and 165 and therefore thevolume of air which these can transfer to housing 125.

With the line 148 connected to the line 92, when'the output from chamber137 is present, this fluid under pressure is applied through the checkvalve 153 (with check valve 153 operating normally) into the chamber 170to move the diaphragm 161 toward the end of the tube 157 which is in thechamber 159. The diaphragm 161 is shown in its normal set pointposition, in other words in position for the nominal time for the basictimer 125. When the output through check valve 153 moves the diaphragm161 toward the tube 157, there is a flow across restriction 158 and thisflow is added into the chamber of housing 125 and helps to move thediaphragm 126 toward the tube 127 faster. The effective volume ofhousing 160 is normally l/lOth to l/5th of the housing 125 so that thediaphragm 126 has not finished its travel when diaphragm 161 hasfinished its travel, but movement of the diaphragm 126 is initiallyspeeded up. The restriction orifice 158 prevents the input pressure fromdiaphragm 161 acting on diaphragm 126 from increasing too much, whichwould actuate the valve 134 to close.

The position ofthe diaphragm 161 and the diaphragm 165A'is determined bytime. As shown the pressure signal has been removed from line 90, whichis in turn a signal from a vehicle detector, as illustrated, for thesection 56A. A sufficient time so the diaphragm moved to its normalposition before actuation of the timer. Any pressure in set point linewill cause diaphragm 161 to be moved toward tube 157 and if thediaphragm 161 has not moved back to its normal position before thesignal from line 148 is present the diaphragm 161 will provide less airto housing than it does normally.

Thus, if the diaphragm 161 has been displaced toward the end of tube 157by pressure in the set point line 90 at the time that the pressureappears on the line 51AL to trigger the timer, the time of operation forthe diaphragm 126 will be a longer period of time than normal becausethere will be less air supplied by the movement of diaphragm 161 throughhousing urging the diaphragm 126 to move. If the position of the diaphragm 161 is displaced toward tube 157 from its normal position and thetime period of basic timer 125 is longer than normal and the vehiclewill be controlled to run more slowly.

The housing and internal diaphragm is used for speeding up the timeperiod of the diaphragm 126 from its normal position, and this action isfor control of the guideway sections comprising the overspeed block. Theouter surface of diaphragm 165A is open to duct pressure, and once apressure signal is removed from the line 90, the check valve 167 ofcourse closes, (as does the check valve 169) and the duct pressureacting on diaphragm 165A will tend to bleed any additional air inchamber 164 through the restrictions 163, and 158 and out throughrestriction 130. However, if the timer is triggered by' a signal in line51AL before the diaphragm 165A returns to its-normal position, thediaphragm 165A adds air to the chamber'in housing 125 and makes thediaphragm 126 sweep faster than normal to thus cause a faster or shorterthan normal time period.

The recovery time for the diaphragm 161 to move to its normal positionis determined by the restriction 171 and the pressure in line 128because the check valve 153 will operate to close when output fromchamber 137 is zero and diaphragm 161 moves toward normal position. Therecovery time for the diaphragm 165A is determined by the orifice 163and the pressure in line 128. The time'for full recovery of thediaphragm 165A is relatively long, and is designed to be the time itnormally takes a vehicle to run about 17 guideway sections at nominalspeed. These sections are in the overspeed block of the spacing control.

Thus, where the signal from line 90 is present, the diaphragm 161immediately moves to position with the diaphragm extended toward thetube 157, and the diaphragm 165A also is extended out from normal. Assoon as the signal from line 90 is removed the dia' phragm 161 movestoward its normal position. Additional variation in the time period ofbasic timer 125 can be made by other regulation of inputs or pressures,if desired.

The housing 125 and sweep diphragm 126 form a fixed volume quantity andby varying the pressures on the inlet or outlet of the housing the timeperiod for sweeping the volume can be changed. The response with thistype of device is immediate. The signal is sharply defined as either onor off.

A fully pneumatic start-stop module is shown in FIG. 8. If a vehicle isinhibited in the stop block wherein neither the levitation valves northe thrust valves are actuated so that the vehicle will stop, some meansof again levitating the vehicle is necessary. The vehicle and the valvesutilized therewith, as shown and explained in connection with the valvesdescribed in US. Pat. application Ser. No. 37,691 require a levitationpressure signal for automatically opening of the valves. If the vehicleis delevitated completely, this pressure signal is not present, and whenthe stop block passes, the vehicle would not again normally start unlesssome means for doing so are provided.

As shown in FIG. 8, the OR gate 76 which was the four input OR gate,includes the input lines 55AL and 57AL, which carry the signals fromdetectors 55A and 57A respectively, form a two input OR gate using ashuttle valve 197 inside a chamber 195. The lines 56AL and 58AL carrythe signals from the vehicle detectors 56A and 58A, into a chamber 196having a shuttle valve 200 forming an OR gate.

The four input OR gate 76 then includes a pair of tubes 201 and 202,which are diametrically opposed, and lead from chambers 195 and 196,respectively. A shuttle valve 203 is positioned between the tubes 201and 202 to form another OR gate. The OR gate 76 has four inputs, and asignal from any one of the input lines will actuate the OR gates so thatthere is fluid under pressure in the passageway 204 leading into fluidamplifier 78. The fluid amplifier includes a chamber 205 that is dividedwith a flexible diaphragm 206 that operates an inhibit valve 207, whichhas one head 208 that controls fluid flow through an opening leadingfrom a duct pressure area 209. The stem of valve 207, has the same crosssection as that shown in FIG. 7A, and extends across a passageway 210that forms the outlet for the fluid amplifier and is connected withsuitable conduits to the control ports of the valves to be controlled.Connection conduits open to the passageway 210 are conduits such as 21and 22 shown in FIG. 1. In FIG. the conduit is numbered 77. The valve207 controls passage of pressurized air from the duct pressure chamber209 into the passageway 201 and thus into the control conduits for therespective levitation and thrust valves. When the valve 207 is actuatedbecause of the pressure of a pressure signal in any one of the lines55AL through 58AL, the valve will be moved to position wherein ductpressure will be present in passageway 210, and the valves controlledthereby would be inhibited from actuating.

The valve 207 also has a head 212 that controls flow of fluid underpressure between passageway 210 and a duct 211. The duct 211 opens intoan annular chamber surrounding a venturi 83. The venturi 83 opens toatmosphere through the deck 13, in the usual situation. Flow through theventuri 83 causes a negative pressure in duct 211, and thereby, when thehead 212 is in its solid line position, a negative pressure inpassageway 210. The negative pressure will cause opening of the valvesto which the signal line or conduit open to passageway 210 is connected.The venturi is actuated through a start valve assembly illustratedgenerally 216. The start valve assembly includes the OR gate 79, havingthe input through a line 80, and the line 54AL which carries the signalfrom detector 54A in this example. The OR gate 79 again is the shuttlevalve type, and is mounted in a chamber 218 that is open through a smallorifice 219 in one wall that opens to one side of a spring loadeddiaphragm 220 operating in a separate chamber. A check valve 220Apermits the diaphragm 220 to move to its position as shown in FIG. 8under the action of spring 2203 when there is no pressure on eitherlines 80 or 54AL. The diaphragm 220 controls a valve member 221 that hasa head 222 for preventing or permitting pressure to pass into theinterior chamber 223 in which the valve 221 operates. Duct pressure ispresent in the area outside of the valve and surrounding the valve head222. The orifice 219 acts as a time delay 81 so that even though apressure signal may be present in either line 80 or 54AL, a time ofactuation before the valve 221 is operated will permit a time delaybetween the appearance of a signal at line 54AL or line 80 and theactuation of the venturi 83.

Th lines 55AL through 58AL carry the stop block inhibit signals for thecorresponding sections of track as described above, and if the vehicledetector 53A continues to supply a signal on line 80, after the timedelay as the signal bleeds through orifice 219, the diaphragm 220 willmove a sufficient distance to actuate the valve 221 so that the head 222moves away from its closed position and fluid under duct pressure willbe supplied into chamber 223 and will flow out through the venturi 83causing a negative pressure in passageway 211. Assuming then that thestop block inhibit signals have been removed (lines 55AL 58AL no longercarry signals), the valve 212 will be in its solid line position and thesuction or negative pressure caused in chamber 211 will be appliedthrough the passageway 210 to the valves on line 77 opening these valvesand levitating the vehicle that is above the valves.

Again if there is an inhibit signal on or in passageway 210, or in otherwords a pressure signal coming from the chamber 209, this will also besuppled to the OR gate 96 to inhibit the thrust valves 53D. When thesignal on 54AL disappears the diaphragm 220 returns under action of thespring, because of a passageway 225 which leads to atmospheric pressureand lets the diaphragm move back through the check valve 221.

The train module 73 is shown in FIG. 9, and is merely an inhibit valvewhich prevents the output signal from the vehicle detector 53A alongline 100 from being applied to the trailing guideway section controls,if there is also a signal at the vehicle detector for the guidewaysection behind the section on which the detector is being actuated. Inthis instance the inhibit signal comes along the line 52AL which leadsfrom the detector 52A. Thus if there is a signal in line 52AL, it entersthe chamber 228, and acts on the diaphragm 229 to move a valve 227 toblock the pressure signal coming from the detector 53A through the line100. When the inhibit signal from a trailing guideway section detectordisappears, valve 227 will be moved to its solid line position as shownin FIG. 9 and the signal from the vehicle detector 53A will be appliedthrough line 101A to the OR gate 76 in the start-stop module for theguideway section 52 making this section part of the stop block ofguideway sections following a train of vehicles.

In H6. 10, there is shown a schematic representation of an applicationof the speed and spacing control concept to a merge line setup, foracceleration guideway for starting a vehicle or merging two guideways,and also for a system where there are two intersecting guideways, sothat proper control can be maintained to insure that there will not beany vehicle collisions. The schematic figure shows a vehicle illustratedgenerally at 230, positioned on a starting section 232 of a merging oracceleration guideway 231. The starting section could be, for example, astation berth where the vehicle 230 is being loaded. Ahead of thevehicle 230 in merging guideway 23]., there are a number of guidewaysections identically numbered with corresponding numbers so that of themain line guideway such as that shown in FIG. 2, and indicated in FIG.at 233. In order to utilize the speed and spacing controls in theacceleration or merging guideway for length of each of the accelerationguideway sections, for example the sections 32M, 33M, 34M, 35M etc. arebased on equal time intervals of vehicle travel in the correspondingsections of the main line guideway 233. For example, the length of timefor the starting vehicle 230 to traverse the short merging guidewaysection 32M will be the same as the length of time for a vehicle movingat nominal speed to traverse the main line section 32. The thrust valvesin sections 32M (which stands for merge), 33M, 34M, etc. have sufficientthrust to start the vehicle 230, and get it moving slowly. As a vehiclethat is traveling on the main line moves along, a stop block slow blockand overspeed block are following along as previously explained. Thecontrol signals that cause the stop block slow block and overspeed blockare transferred with suitable pneumatic connections illustratedgenerally at 234 to corresponding sections of the merging guideway. Forexample, if the vehicle 57 is positioned at guideway section 52, whichis right at the merge point, and is tripping vehicle detector 53A, aspreviously explained, this would insure that the stop block of sections51, 50, S9, and 48 would be reflected into the sections 51M, 50M, 49Mand 48M of the merge guideway. Likewise, the slow block would bereflected into sections 47M, 46M, 45M and 44M, and the vehicle 230 couldbe following in position along the slow block. Assuming that the vehicleis positioned on guideway section 43M and his tripped detector 44MA, thestop block behind this vehicle 230 would be reflected into mergesections 42M, 41M, 40M and 39M, and also reflected into thecorresponding sections on the main guideway, to prevent any othervehicle on the main guideway from entering the stop block on the mainguideway set up by vehicle 230 as it moves along. This keeps anaccelerating, merging vehicle from merging into a main line vehicle, andalso keeps a second main line vehicle, therefore, from merging into therear of the accelrating vehicle on the merge guideway. Thus thedetectors and other controls are present on the merge guideway just asthey are on the main line guideway.

Also as a further function of the merging control, there has to be asufficient opening or space on the main line guideway for the mergedvehicle to enter into the track at the time it reaches the section 52and still be behind a stop block of a lead vehicle and there should bespace for a stop block so the merged vehicle doesns stop a secondvehicle on the main guideway. The section 32 is a position where themerging vehicle 230 can stay until detectors indicated generally at 235,which represent the number of vehicle detectors necessary to indicate aproper vehicle spacing, give a desired clear signal indicated at 236, tothe control connections to the merging guideway. This then will alsoinitiate the vehicle start control such as the venturi previouslydescribed to levitate the vehicle 230 and to start it moving along thetrack sections 32M 51M. Again if there is a main line vehicle passingby, the controls are tied in with suitable connections into the mergeguideway valves to insure that there is not a collision at the point ofmerger.

A further schematic showing of the pneumatic connections that arenecessary for both the normal main line guideway and the use of themerged guideway, FIG. 11 is a schematic diagram showing eight conduits,which are represented by lines, for carrying all pneumatic signals tothe guideways.

The vehicle detectors are indicated by the section number with an Asuffix, for example 45A and 45MA for the merge track detectors. Theoutput connections are indicated at 237, and the input connections areindicated at 238. The input connections go to control the thrust andcruise valves. The thrust valves are shown by a solid black arrow in theschematic drawing, and the cruise valves are shown by an open orunfilled arrow head. The six input lines to the input connections 238are represented in FIG. 5, such as the four input lines leading to theOR gate 76, the line leading to the OR gate 79, and the line whichconnects from the output of each vehicle detector to the inputconnections. The line 80 is labeled in FIG. 11, as is the line whichgoes to the other output connections. The module in FIG. 11 does notshow the train module. However this can be coupled in as desired ornecessary. Only a typical showing is made. By connecting the conduitsbetween the merge and main line guideways, the controls are reflectedfrom each of the guideways back into the other guideways. The sectionsthus are tied together for positive control. In order to give the clearsignal 236, the input lines from the required number of vehicledetectors in the track sections prior to the merge point are used in thecontrol module 236.

If vehicle 230 starting out on the merge guideway fails to respond ormove properly the merge vehicle can be aborted and stopped by use of acontrol 246 that disables all connections between the two guideways anddisables all valves in the merge section. The control 246 can, forexample, include a separate timer which is initiated when vehicle 230 isstarted to move and which is disabled when the vehicle 230 passed amerge guideway section, for example section 46M. If the timer period ofthe separate timer elapses before the vehicle reaches section 46M thedisabling function of control 246 would occur and vehicle 230 would bestopped, or aborted. Also the controls 246 may be used to sound an alarmor indicator when a vehicle is aborted, and to keep all valves in themerge track disabled until the aborted vehicle is removed or restarted.

Referring also to FIG. 10, a right angle intersecting guideway 240 canbe interlocked with the main guideway to control movement ofintersecting vehicles merely by coupling the controls between the mainguideway sections and the intersecting guideway 240, which aredesignated with the letter S. The interconnection would be as shown inFIG. 11 for the merging track.

The spacing therefore can be used for merging of crossing guideways aswell as linear guideways, and of course the guideway construction is notcritical to the invention. Tracks of or monorails also are meant to beincluded in the term guideway. Also the propulsion or thrust could belinear induction motors or other devices. In speed and spacing controlthe stop block signals and slow signals can also be used for reversethrust or brakes. For example on a rail guided vehicle brakes could beapplied if desired to control spacing.

The reference to line, conduits or tubes connecting the various operablepneumatic control elements is meant to refer to a suitable tubularconnection that will carry the flow of fluid under pressure used as asignal.

The term vehicle module means either a single vehicle or a train ofconnected or coupled vehicles that may be treated as one vehicle forspacing purposes, that is, the stop, slow and over-speed blocks aremaintained at the trailing end of the module.

Both the cruise valves and thrust valves are automatically open normallybut can be inhibited or opened by signals on the lines 74 and 75 in FIG.5. Pressure signals will inhibit the valves and vacuum signals will openthe valves to supply or deny power to the vehicles.

What is claimed is:

l. A control system for vehicle modules comprising one vehicle or aplurality of connected vehicles movable on a guideway means, comprisingmeans effectively dividing said guideway into guideway control sectionsincluding vehicle module detector means mounted on said guideway foreach guideway control section to detect a vehicle module positionrelated to its associated guideway control section, control means actingin response to said vehicle module detector means including meansindicating the speed of movement of a vehicle module from a firstvehicle module detector means to a second spaced vehicle module detectormeans in relation to a reference set point speed between said first andsecond vehicle module detector means, means to adjust the speed ofvehicle module movement subsequent to movement past the second vehiclemodule detector means in response to the differencee in indicated speedand the reference speed of said means for indicating vehicle modulespeed, and means to adjust said reference speed in response to presenceof a vehicle module on a preselected portion of the guideway meansspaced in the direction of vehicle module movement from said secondvehicle module detector means.

2. The control system of claim 1, and means acting in response to saidvehicle module detector means to prevent a following vehicle module fromadvancing closer than a preselected number of guideway sections to aleading vehicle module comprising means to stop a vehicle module when itmoves closer than said preselected number to a leading vehicle module.

3. The control system for vehicles according to claim 1, wherein saidvehicle modules are levitated, and wherein means are provided forlevitating and propelling said vehicle modules comprising normallyautomatically opening valve means in said guideway means for providinglevitation fluid under pressure and propulsive fluid under pressure, andmeans to prevent a following vehicle module from advancing closer than apreselected number of guideway sections to a leading vehicle modulecomprising means to prevent levitation and propulsion fluid underpressure from being supplied to a following vehicle module closer than apreselected amount behind a leading vehicle module.

4. The control system of claim 3 wherein said means indicating the speedof movement includes timer means having a time period to provide theindication of the set point speed between the activation of the firstvehicle detector means by one vehicle module and the activation of thesecond vehicle detector means spaced on the guideway in direction ofmovement of said vehicle module by said one vehicle module, means tonormally supply propulsive power to said one vehicle module as ittraverses the guideway, and means to prevent propulsive power from beingsupplied to said one vehicle module if said one vehicle module activatesthe second detector means before the time period of the timer means hasexpired.

5. A control system for vehicle modules comprising one vehicle or aplurality of connected vehicles moving along a guideway means,comprising means effectively dividing said guideway means into guidewaycontrol sections including vehicle module detector means mounted on saidguideway for each section to detect a vehicle module position inrelation to its associated guideway control section, control meansacting in response to said vehicle detector means cooperating betweenthe guideway means and the vehicle module to prevent a followingseparate vehicle module from advancing into a stop block comprising apreselected number of guideway control sections trailing a leadingvehicle module, said control means including timer mans to time speed ofmovement of a vehicle module from one said vehicle module detectors to asecond vehicle module detector in relation to a selected time per iod,said second vehicle module detector being a preselected distance fromsaid first vehicle module detector and spaced in the direction ofmovement of vehicle modules, means to adjust the speed of said separatevehicle module in response to the differences between elasped time ofthe separate vehicle module travel between said vehicle module detectorsand the selected time period, said timer means having an adjustable timeperiod, and means to adjust the time period of said timer means inrelation to a signal from a vehicle detector indicating the presence ofavehicle module in a preselected guideway section associated with eachtimer.

6. The control system of claim 5, and means acting between said guidewayand said vehicle module to control propulsion of the vehicle module asit traverses a particular guideway section, and wherein said means toadjust the separate vehicle module speed in response to the time oftravel thereof between said first and second vehicle detector meansincludes means to prevent propulsive thrust from being supplied to theseparate vehicle module when the vehicle module travels between saiddetector means in less than a preselected time.

7. A control system for vehicle modules comprising one vehicle or aplurality of connected vehicles moving along a guideway means,comprising means effectively dividing said guideway means into guidewaycontrol sections including vehicle module detector means mounted on saidguideway for each section to detect a vehicle module position inrelation to its associated guideway control section, control meansacting in response to said vehicle detector means to prevent a fol-'lowing separate vehicle module from advancing into a stop blockcomprising a preselected number of guideway control sections trailing aleading vehicle module, said control meansincluding adjustable periodtimer means started by a signal from a first vehicle detector detectingsaid separate vehicle module to measure the time of movement of saidseparate vehicle module from said first of said vehicle module detectorsto a second vehicle module detector in relation to the timer timeperiod, said second vehicle module detector being a preselected distancefrom said first vehicle module detector and spaced in the direction ofmovement of vehicle modules, power means to change the speed of saidvehicle module in response to differences between the time of vehiclemodule travel between said first and second vehicle module detectors andthe associated timer means time period, and means to adjust theassociated timer means time period as a function of elapsed timesubsequent to the passage of said stop block behind a leading vehiclemodule previously actuating said first vehicle detector means and saidtimer means.

8. The control system of claim 7, said timer means including a basictimer having a normal time period, and said first means to adjustincludes means to adjust the time period first to a longer time intervalafter passage of said stop block.

9. The control means of claim and second means to adjust the time periodto a shorter time interval for a preselected time after the first meansto adjust the time period is no longer effective.

10. The control system of claim 1 and a second guideway meansintersecting with said first guideway means, said second guideway meansbeing divided into second guideway section, each of said second guidewaysections including vehicle module detector means, and control means forregulating the spacing of vehicle modules in said second guidewaysections, said control means and vehicle module detector means beinginterconnected between corresponding sections of said first and secondguideways in relation to the merge point between said first guidewaymeans and said second guideway means whereby vehicle module detectormeans in either guideway controls vehicle modules in correspondingguideway sections of both guideway means.

11. The combination as specified in claim 10 where said second guidewaymeans comprises an acceleration guideway means, and wherein the sectionsof said acceleration guideway are different inlength than thecorresponding sections of the main guideway means except immediatelyadjacent the merge point, and said control means including timer meansto determine elapsed time for movement of a vehicle module along thecorresponding guideway sections and at least adjacent the mergingguideway sections, the elapsed time for a vehicle module to traverse aninterconnected section on either the intersecting guideway issubstantially the same.

12. A control system for vehicle modules comprising one vehicle or aplurality of connected vehicles movable on a guideway means, comprisingmeans effectively dividing said guideway into guideway control sections,power means on the guidway for propelling said vehicle modules normallysupplying power to a vehicle in a guideway section, said meanseffectively dividing said guideway including vehicle module detectormeans mounted on said guideway for each section to detect a vehiclemodule position relative to its associated guideway section, and controlmeans responsive to said vehicle detector means controlling said powermeans to regulate the spacing between a leading vehicle module and atrailing vehicle module, said power means comprising fluid underpressure to levitate and propel vehicle modules, valve means to controlflow of fluid under pressure from a source to levitate said vehiclemodules, and said control means includes means to prevent at least someof said valve means from operating in a preselected number of guidewaysections behind said leading vehicle module.

13. The control system of claim 12, and means acting in response to saidvehicle detectors to prevent a following vehicle module from advancingcloser than a stop block comprising a preselected number of guidewaysections to a leading vehicle module comprises means to stop a vehiclemodule when it moves closer than a preselected number of guidewaysections to a leading vehicle module.

14. The control system according to claim 13, wherein said means toprevent a following vehicle from advancing closer than a preselectednumber of sections comprises OR gate means delivering disabling andbraking signal means to said power means, said OR gate means having aplurality of inputs equal to the preselected number of guideway sectionsin said stop block, and means to operably connect the signal outputs ofthe vehicle module detector means of the guideway sections comprisingthe stop block to the inputs of said OR gate, said OR gate includingmeans to deliver said disabling signal in response to a vehicle detectorsignal at any one of said OR gate inputs.

15. The system of claim 14 wherein said vehicle module comprises asingle vehicle not substantially longer than the length of each guidewaysection.

16. The system of claim 14 wherein said vehicle module comprises aplurality of vehicles connected together and, means to prevent a vehiclemodule detector signal of one guideway section from entering itsassociated OR gate means until there is no vehicle module detectorsignal from the vehicle detector next adjacent and trailing said oneguideway section.

17. The system of claim 13 and means to adjust the preselected timerperiod of said timer means to be longer in a selected number of timersassociated with guideway sections immediately trailing said stop block.

18. The system of claim 13 and means to adjust the timer period of saidtimer to a shorter time period for the timers associated with selectedguideway sections spaced a selected number of guideway sections from thelast guideway section comprising a stop block for a leading vehicle.

19. The system of claim 13 and means to provide a power start signal tosaid power means in response to one vehicle module detector meanssignal, from a guideway section other than a section comprising saidstop block, a preselected length of time after the one vehicle moduledetector means delivers a signal indicating presence of a vehicle moduleon its associated guideway section.

1. A control system for vehicle modules comprising one vehicle or aplurality of connected vehicles movable on a guideway means, comprisingmeans effectively dividing said guideway into guideway control sectionsincluding vehicle module detector means mounted on said guideway foreach guideway control section to detect a vehicle module positionrelated to its associated guideway control section, control means actingin response to said vehicle module detector means including meansindicating the speed of movement of a vehicle module from a firstvehicle module detector means to a second spaced vehicle module detectormeans in relation to a reference set point speed between said first andsecond vehicle module detector means, means to adjust the speed ofvehicle module movement subsequent to movement past the second vehiclemodule detector means in response to the differencee in indicated speedand the reference speed of said means for indicating vehicle modulespeed, and means to adjust said reference speed in response to presenceof a vehicle module on a preselected portion of the guideway meansspaced in the direction of vehicle module movement from said secondvehicle module detector means.
 2. The control system of claim 1, andmeans acting in response to said vehicle module detector means toprevent a following vehicle module from advancing closer than apreselected number of guideway sections to a leading vehicle modulecomprising means to stop a vehicle module when it moves closer than saidpreselected number to a leading vehicle module.
 3. The control systemfor vehicles according to claim 1, wherein said vehicle modules arelevitated, and wherein means are provided for levitating and propellingsaid vehicle modules comprising normally automatically opening valvemeans in said guideway means for providing levitation fluid underpressure and propulsive fluid under pressure, and means to prevent afollowing vehicle module from advancing closer than a preselected numberof guideway sections to a leading vehicle module comprising means toprevent levitation and propulsion fluid under pressure from beingsupplied to a following vehicle module closer than a preselected amountbehind a leading vehicle module.
 4. The control system of claim 3wherein said means indicating the speed of movement includes timer meanshaving a tiMe period to provide the indication of the set point speedbetween the activation of the first vehicle detector means by onevehicle module and the activation of the second vehicle detector meansspaced on the guideway in direction of movement of said vehicle moduleby said one vehicle module, means to normally supply propulsive power tosaid one vehicle module as it traverses the guideway, and means toprevent propulsive power from being supplied to said one vehicle moduleif said one vehicle module activates the second detector means beforethe time period of the timer means has expired.
 5. A control system forvehicle modules comprising one vehicle or a plurality of connectedvehicles moving along a guideway means, comprising means effectivelydividing said guideway means into guideway control sections includingvehicle module detector means mounted on said guideway for each sectionto detect a vehicle module position in relation to its associatedguideway control section, control means acting in response to saidvehicle detector means cooperating between the guideway means and thevehicle module to prevent a following separate vehicle module fromadvancing into a stop block comprising a preselected number of guidewaycontrol sections trailing a leading vehicle module, said control meansincluding timer mans to time speed of movement of a vehicle module fromone said vehicle module detectors to a second vehicle module detector inrelation to a selected time period, said second vehicle module detectorbeing a preselected distance from said first vehicle module detector andspaced in the direction of movement of vehicle modules, means to adjustthe speed of said separate vehicle module in response to the differencesbetween elasped time of the separate vehicle module travel between saidvehicle module detectors and the selected time period, said timer meanshaving an adjustable time period, and means to adjust the time period ofsaid timer means in relation to a signal from a vehicle detectorindicating the presence of a vehicle module in a preselected guidewaysection associated with each timer.
 6. The control system of claim 5,and means acting between said guideway and said vehicle module tocontrol propulsion of the vehicle module as it traverses a particularguideway section, and wherein said means to adjust the separate vehiclemodule speed in response to the time of travel thereof between saidfirst and second vehicle detector means includes means to preventpropulsive thrust from being supplied to the separate vehicle modulewhen the vehicle module travels between said detector means in less thana preselected time.
 7. A control system for vehicle modules comprisingone vehicle or a plurality of connected vehicles moving along a guidewaymeans, comprising means effectively dividing said guideway means intoguideway control sections including vehicle module detector meansmounted on said guideway for each section to detect a vehicle moduleposition in relation to its associated guideway control section, controlmeans acting in response to said vehicle detector means to prevent afollowing separate vehicle module from advancing into a stop blockcomprising a preselected number of guideway control sections trailing aleading vehicle module, said control means including adjustable periodtimer means started by a signal from a first vehicle detector detectingsaid separate vehicle module to measure the time of movement of saidseparate vehicle module from said first of said vehicle module detectorsto a second vehicle module detector in relation to the timer timeperiod, said second vehicle module detector being a preselected distancefrom said first vehicle module detector and spaced in the direction ofmovement of vehicle modules, power means to change the speed of saidvehicle module in response to differences between the time of vehiclemodule travel between said first and second vehicle module detectors andthe associated timer means time period, and means To adjust theassociated timer means time period as a function of elapsed timesubsequent to the passage of said stop block behind a leading vehiclemodule previously actuating said first vehicle detector means and saidtimer means.
 8. The control system of claim 7, said timer meansincluding a basic timer having a normal time period, and said firstmeans to adjust includes means to adjust the time period first to alonger time interval after passage of said stop block.
 9. The controlmeans of claim 10 and second means to adjust the time period to ashorter time interval for a preselected time after the first means toadjust the time period is no longer effective.
 10. The control system ofclaim 1 and a second guideway means intersecting with said firstguideway means, said second guideway means being divided into secondguideway section, each of said second guideway sections includingvehicle module detector means, and control means for regulating thespacing of vehicle modules in said second guideway sections, saidcontrol means and vehicle module detector means being interconnectedbetween corresponding sections of said first and second guideways inrelation to the merge point between said first guideway means and saidsecond guideway means whereby vehicle module detector means in eitherguideway controls vehicle modules in corresponding guideway sections ofboth guideway means.
 11. The combination as specified in claim 10 wheresaid second guideway means comprises an acceleration guideway means, andwherein the sections of said acceleration guideway are different inlength than the corresponding sections of the main guideway means exceptimmediately adjacent the merge point, and said control means includingtimer means to determine elapsed time for movement of a vehicle modulealong the corresponding guideway sections and at least adjacent themerging guideway sections, the elapsed time for a vehicle module totraverse an interconnected section on either the intersecting guidewayis substantially the same.
 12. A control system for vehicle modulescomprising one vehicle or a plurality of connected vehicles movable on aguideway means, comprising means effectively dividing said guideway intoguideway control sections, power means on the guidway for propellingsaid vehicle modules normally supplying power to a vehicle in a guidewaysection, said means effectively dividing said guideway including vehiclemodule detector means mounted on said guideway for each section todetect a vehicle module position relative to its associated guidewaysection, and control means responsive to said vehicle detector meanscontrolling said power means to regulate the spacing between a leadingvehicle module and a trailing vehicle module, said power meanscomprising fluid under pressure to levitate and propel vehicle modules,valve means to control flow of fluid under pressure from a source tolevitate said vehicle modules, and said control means includes means toprevent at least some of said valve means from operating in apreselected number of guideway sections behind said leading vehiclemodule.
 13. The control system of claim 12, and means acting in responseto said vehicle detectors to prevent a following vehicle module fromadvancing closer than a stop block comprising a preselected number ofguideway sections to a leading vehicle module comprises means to stop avehicle module when it moves closer than a preselected number ofguideway sections to a leading vehicle module.
 14. The control systemaccording to claim 13, wherein said means to prevent a following vehiclefrom advancing closer than a preselected number of sections comprises ORgate means delivering disabling and braking signal means to said powermeans, said OR gate means having a plurality of inputs equal to thepreselected number of guideway sections in said stop block, and means tooperably connect the signal outputs of the vehicle module detector meansof the guideway sections comprising the stop block to the inputs of saidOR gate, said OR gate including means to deliver said disabling signalin response to a vehicle detector signal at any one of said OR gateinputs.
 15. The system of claim 14 wherein said vehicle module comprisesa single vehicle not substantially longer than the length of eachguideway section.
 16. The system of claim 14 wherein said vehicle modulecomprises a plurality of vehicles connected together and, means toprevent a vehicle module detector signal of one guideway section fromentering its associated OR gate means until there is no vehicle moduledetector signal from the vehicle detector next adjacent and trailingsaid one guideway section.
 17. The system of claim 13 and means toadjust the preselected timer period of said timer means to be longer ina selected number of timers associated with guideway sectionsimmediately trailing said stop block.
 18. The system of claim 13 andmeans to adjust the timer period of said timer to a shorter time periodfor the timers associated with selected guideway sections spaced aselected number of guideway sections from the last guideway sectioncomprising a stop block for a leading vehicle.
 19. The system of claim13 and means to provide a power start signal to said power means inresponse to one vehicle module detector means signal, from a guidewaysection other than a section comprising said stop block, a preselectedlength of time after the one vehicle module detector means delivers asignal indicating presence of a vehicle module on its associatedguideway section.
 20. A control system for vehicle modules comprisingone vehicle or a plurality of connected vehicles movable on a guidewaymeans, comprising power means on the guideway for propelling saidvehicle modules, means actuated to normally supply power to a vehiclemodule on the guideway, vehicle module detector means mounted on saidguideway in spaced locations therealong to detect a vehicle module inposition on the guideway, control means responsive to said vehicledetector means controlling said power means in portions of said guidewayto regulate the spacing between a leading vehicle module and a trailingvehicle module in said portion of said guideway, including timer meansinitiated by detection of a vehicle module by one of said vehicle moduledetectors to determine the time of movement of a vehicle module fromsaid one of said vehicle module detectors to a selected second vehiclemodule detector in relation to a selected set point time period of saidtimer means, means to control the power means to regulate the speed ofsaid vehicle module in response to a difference between the elapsed timeof vehicle module travel between said first and second vehicle moduledetectors and the set point time period, and means to adjust the setpoint time period of said timer means in response to passage of avehicle module.